Many electrical connectors include latch means for securely but releasably retaining a pair of electrical connector housings in a mated condition. More particularly, these prior art connectors include mateable pairs of molded plastic housings, each of which is constructed to receive a plurality of terminals therein. The terminals of one housing electrically contact the terminals of the other housing when the housings are in their mated condition.
Unitarily molded electrical connector housings are generally considered desirable in that they yield certain manufacturing efficiencies, simplify the installation and use of the connector and minimize inventory management problems. Thus, it is often desirable to unitarily mold an entire electrical connector housing, including the latch means thereof.
Many electrical connectors are used in environments where they will be repeatedly connected and disconnected by personnel having relatively little familiarity with the mechanics and intended use of the connector. For example, electrical connectors often are employed in photostatic copiers and other office equipment that may periodically be serviced by field technicians or by the office staff that uses the copier or other such business machine. Field technicians often are not adequately trained on the proper usage of every electrical connector they are likely to encounter. Office personnel using various business machines typically have even less training and familiarity with the electrical connectors they may periodically be required to connect and/or disconnect. This lack of familiarity with the electrical connectors manipulated by field or office personnel can result in overstressing the latch mechanisms employed to lockingly but releasably retain electrical connector housings in a mated condition. For example, inexperienced field personnel may unintentionally bias a latch mechanism too far, thereby breaking or reducing the effectiveness of the latch.
Electrical connector housings have been developed to minimize this potential for overstressing the latch structures thereof. For example, U.S. Pat. No. 4,462,654 which issued to Aiello on July 31, 1984 shows a latch integrally and pivotally connected to a housing. The forward end of the latch extends from the pivoted connection to define a latch portion which is engageable with corresponding structure on a mateable housing. The rearward end of the latch member extends in the opposite direction from the pivot and includes an overstress stop which is pivotable into a lug or wall on the electrical connector housing. Contact between the overstress stop and the lug or wall of the electrical connector housing is intended to limit the amount of rotation around the pivot point during the normal engagement of the electrical connector housings. Although this construction may control the amount of pivoting during proper use of the electrical connector, it provides no positive anti-stress protection adjacent the forward end of the latch member. Thus, field personnel inexperienced with the intended operation of the latch shown in U.S. Pat. No. 4,462,654 could apply rotatable pressure to the forwardmost end of the latches for either locking or releasing the electrical connector housings to one another. Such rotational forces exerted on the forward end of the latch member could overstress the latch, thereby causing the latch to break or be of reduced effectiveness.
Another problem that can be encountered when inexperienced field personnel employ electrical connectors is referred to by persons skilled in this art as "fish-hooking". In particular, the latch members on many electrical connectors are cantilevered structures that effectively function as fishhooks which may catch insulated leads as the electrical connector is being inserted into or removed from an electrical apparatus. Fishhooking can damage an adjacent circuit that is unintentionally caught by the latch structure of the electrical connector housing. Additionally, an attempt to operate the latch structure while a wire or other lead is in its fishhooked engagement can permanently damage the latch.
Several electrical connector housings have been manufactured to avoid such fishhooking problems. For example, U.S. Pat. No. 4,272,145 which issued to LaDuke on June 9, 1981 includes a guard plate disposed in proximity to a lever arm to prevent unintentional fishhooking of wires that may be disposed in proximity to the electrical connector housing. The electrical connector housing shown in U.S. Pat. No. 4,272,145 provides no anti-overstress protection, and the anti-overstress protection shown in the above-described U.S. Pat. No. 4,462,654 could not readily be incorporated into the design of U.S. Pat. No. 4,272,145.
Other electrical connectors with integral latch structures therein are shown in U.S. Pat. No. 4,582,378 which issued to Fruchard on Apr. 15, 1986; U.S. Pat. No. 4,640,566 which issued to Matsusaka on Feb. 3, 1987; U.S. Pat. No. 4,105,275 which issued to Dickson et al. on Aug. 8, 1978; and U.S. Pat. No. 3,179,738 which issued to DeLyon on Apr. 20, 1965.
In view of the above, it is an object of the subject invention to provide an electrical connector housing constructed to positively prevent overstress of the latch structure thereof.
Another object of the subject invention is to provide an electrical connector housing that positively prevents the latch structures from being entangled with insulated conductive leads employed in the vicinity of the connector.
An additional object of the subject invention is to provide an electrical connector housing of simple integrally molded construction which prevents overstress of the latch structures thereof and which prevents fish-hooking of insulated conductive leads.
A further object of the subject invention is to provide an electrical connector housing that cannot be damaged during initial harness work, handling or subsequent use.